In conventional RFID systems of the related art, tags are attached to objects to be identified, and a reader transmits an interrogator signal to the tag and reads a response from the tag. RFID tags can be either passive, active, or battery-assisted passive. An active tag has an on-board battery and periodically transmits its ID signal. A battery-assisted passive tag has a small battery on board and is activated when in the presence of an RFID reader. A passive tag uses radio energy transmitted by the RFID reader to become active and transmit its ID signal.
RFID tags are used in many industries for tracking objects. For example, RFID tags attached to pharmaceuticals can be tracked through warehouses.
The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.